Java log4j2弹簧引导查找can'；无法从application.properties读取属性

我希望log4j2-spring.xml从application.properties文件中读取属性。但log4j2-spring.xml似乎无法读取此信息。我已经读过书来实现这一点

我在这个网站上看到过。我也这样试过。但这对我没有帮助

我的build.gradle是这样的：

plugins {
    id 'org.springframework.boot' version '2.5.0-SNAPSHOT'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
    maven { url 'https://repo.spring.io/milestone' }
    maven { url 'https://repo.spring.io/snapshot' }
}

ext {
    log4j2version = '2.14.1'
}

dependencies {

    compileOnly 'org.projectlombok:lombok:1.18.18'
    annotationProcessor 'org.projectlombok:lombok:1.18.18'

    implementation 'org.springframework.boot:spring-boot-starter'
    implementation 'org.springframework.boot:spring-boot-starter-log4j2'

    implementation "org.apache.logging.log4j:log4j-spring-cloud-config-client:${log4j2version}"
    implementation "org.apache.logging.log4j:log4j-api:${log4j2version}"
    implementation "org.apache.logging.log4j:log4j-core:${log4j2version}"
}

configurations {
    all {
        exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
        exclude group: "ch.qos.logback", module: "logback-classic"
        exclude group: "org.springframework.cloud", module: "spring-cloud-bus"
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    
    <Appenders>
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss:SSS} [%thread] %-5level %logger{2}:%L - %msg%n"/>
        </Console>

        <RollingFile name="CATALINA-FILE" fileName="$${spring:commission.base.path1}/logs/catalina.log"
                     filePattern="$${spring:commission.base.path1}/logs/archived/catalina_%d{yyyy-MM-dd}.log.gz">
            <PatternLayout>
                <Pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{20}:%L - %msg%n</Pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy interval="1"/>
                <SizeBasedTriggeringPolicy size="1 GB" />
            </Policies>
        </RollingFile>
    </Appenders>

    <Loggers>
        <root level="debug">
            <appender-ref ref="CATALINA-FILE"/>
            <appender-ref ref="console"/>
        </root>
    </Loggers>
</configuration>

application.properties文件是：

commission.base.path1=C:/Users/user1/Downloads/demo1
logging.config=classpath:log4j2-spring.xml

spring.cloud.config.enabled=false

log4j2-spring.xml如下所示：

plugins {
    id 'org.springframework.boot' version '2.5.0-SNAPSHOT'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
    maven { url 'https://repo.spring.io/milestone' }
    maven { url 'https://repo.spring.io/snapshot' }
}

ext {
    log4j2version = '2.14.1'
}

dependencies {

    compileOnly 'org.projectlombok:lombok:1.18.18'
    annotationProcessor 'org.projectlombok:lombok:1.18.18'

    implementation 'org.springframework.boot:spring-boot-starter'
    implementation 'org.springframework.boot:spring-boot-starter-log4j2'

    implementation "org.apache.logging.log4j:log4j-spring-cloud-config-client:${log4j2version}"
    implementation "org.apache.logging.log4j:log4j-api:${log4j2version}"
    implementation "org.apache.logging.log4j:log4j-core:${log4j2version}"
}

configurations {
    all {
        exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
        exclude group: "ch.qos.logback", module: "logback-classic"
        exclude group: "org.springframework.cloud", module: "spring-cloud-bus"
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    
    <Appenders>
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss:SSS} [%thread] %-5level %logger{2}:%L - %msg%n"/>
        </Console>

        <RollingFile name="CATALINA-FILE" fileName="$${spring:commission.base.path1}/logs/catalina.log"
                     filePattern="$${spring:commission.base.path1}/logs/archived/catalina_%d{yyyy-MM-dd}.log.gz">
            <PatternLayout>
                <Pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{20}:%L - %msg%n</Pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy interval="1"/>
                <SizeBasedTriggeringPolicy size="1 GB" />
            </Policies>
        </RollingFile>
    </Appenders>

    <Loggers>
        <root level="debug">
            <appender-ref ref="CATALINA-FILE"/>
            <appender-ref ref="console"/>
        </root>
    </Loggers>
</configuration>

---

如何解决这个问题？提前感谢。

问题是您是否需要在Spring云上配置Log4j

问题

如果不是的话，我会说，org.apache.logging.log4j:2.14.1依赖性是一种过分的行为。它带来了您不需要的Spring云依赖性。在某种程度上，我还没有弄清楚，它还与spring-boot-starter-log4j2发生了干涉，导致多次初始化日志上下文，然后作为一个副作用，您在启动时有这个例外，因为spring的属性没有解决

解决方案

请注意，您不需要整个log4jspring云配置客户端甚至spring-boot-starter-log4j2

以下依赖项将设置日志记录上下文：

• log4j
• log4j-slf4j-impl
• log4j弹簧靴

我已经提出了一个建议。变量名略有更改，并且有注释解释每个依赖项的用途

Gradle构建文件摘录

dependencies {

  compileOnly 'org.projectlombok:lombok:1.18.18'
  annotationProcessor 'org.projectlombok:lombok:1.18.18'

  // Spring Boot dependency
  implementation 'org.springframework.boot:spring-boot-starter'
  testImplementation 'org.springframework.boot:spring-boot-starter-test'

  // Logging dependencies

  // Base Log4j 2
  implementation "org.apache.logging.log4j:log4j-api:${log4j2version}"

  // Will resolve spring properties
  implementation "org.apache.logging.log4j:log4j-spring-boot:${log4j2version}"

  // Log4j 2 to Slf4j binder
  implementation "org.apache.logging.log4j:log4j-slf4j-impl:${log4j2version}"
}

应该说，log4j spring boot依赖关系足以从spring配置文件解析查找变量

---

但是，如果您确实需要通过云配置配置Log4J，那么您必须再次仔细查看依赖关系是如何解决的，以及您真正需要哪些依赖关系。

试试这一个$istead$$

fileName=“${spring:commission.base.path1}/logs/catalina.log” filePattern=“${spring:commission.base.path1}/logs/archived/catalina_%d{yyyy-MM-dd}.log.gz”>

实现“org.apache.logging.log4j:log4j spring boot”

在build.gradle中，它现在正在工作

实施

实现'org.springframework.boot:spring-boot-starter-log4j2'

足够使用log4j2版本2.14.1，因为spring引导版本是2.5.0-SNAPSHOT。无需为此显式添加对org.apache.logging.log4j的依赖项

所以我的最终版本是：

plugins {
    id 'org.springframework.boot' version '2.5.0-SNAPSHOT'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
    maven { url 'https://repo.spring.io/milestone' }
    maven { url 'https://repo.spring.io/snapshot' }
}

dependencies {

    compileOnly 'org.projectlombok:lombok:1.18.18'
    annotationProcessor 'org.projectlombok:lombok:1.18.18'

    implementation 'org.springframework.boot:spring-boot-starter'
    implementation 'org.springframework.boot:spring-boot-starter-log4j2'

    implementation "org.apache.logging.log4j:log4j-spring-boot"
}

configurations {
    all {
        exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
    }
}

而无需要将其保存在应用程序中。属性：

spring.cloud.config.enabled=false

---

是的，应该添加log4j spring boot依赖项足以实现spring查找。

尝试将log4j2-spring.xml中的$$转换为单个$@SachinI看到LoggingApplicationListener类初始化记录器两次。第一个默认SpringBoot记录器没有解析的applocation配置属性，因此它尝试查找引发异常的文本路径“${spring:commission.base.path1}/logs/catalina.log”。然后，第二次使用解析路径正确配置的记录器被注入。另外，安装看起来很粗糙，但是找不到更好的例子来说明如何正确使用log4j-spring-cloud-config客户端。